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    Uncertainty analysis in QUAL2E model of Zayandeh-Rood River

    , Article Water Environment Research ; Volume 77, Issue 3 , 2005 , Pages 279-286 ; 10614303 (ISSN) Abrishamchi, A ; Tajrishy, M ; Shafieian, P ; Sharif University of Technology
    Water Environment Federation  2005
    Water-quality modeling and prediction is a complicated task because of inherent randomness and uncertainties associated with various processes and variables throughout the stream environment and the lack of appropriate data. Hence, the results of mathematical models are always approximate, lying within an uncertainty. This paper describes and demonstrates the application of the U.S. Environmental Protection Agency's water-quality model, QUAL2E-UNCAS, to the Zayandeh-Rood River in Iran. First-order reliability analysis is used to examine the variability of predicted water-quality parameters of total dissolved solids, dissolved oxygen, and biochemical oxygen demand. This analysis also... 

    Chemometric-based determination of polycyclic aromatic hydrocarbons in aqueous samples using ultrasound-assisted emulsification microextraction combined to gas chromatography-mass spectrometry

    , Article Journal of Chromatography A ; Volume 1413 , September , 2015 , Pages 117-126 ; 00219673 (ISSN) Ahmadvand, M ; Sereshti, H ; Parastar, H ; Sharif University of Technology
    Elsevier  2015
    In the present research, ultrasonic-assisted emulsification-microextraction (USAEME) coupled with gas chromatography-mass spectrometry (GC-MS) has been proposed for analysis of thirteen environmental protection agency (EPA) polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Tetrachloroethylene was selected as extraction solvent. The main parameters of USAEME affecting the efficiency of the method were modeled and optimized using a central composite design (CCD). Under the optimum conditions (9 μL for extraction solvent, 1.15% (w/v) NaCl (salt concentration) and 10min for ultrasonication time), preconcentration factor (PF) of the PAHs was in the range of 500-950. In order to have a... 

    Assessment of sustainable groundwater resources management using integrated environmental index: Case studies across Iran

    , Article Science of the Total Environment ; Volume 676 , 2019 , Pages 792-810 ; 00489697 (ISSN) Hosseini, S. M ; Parizi, E ; Ataie Ashtiani, B ; Simmons, C. T ; Sharif University of Technology
    Elsevier B.V  2019
    Assessing environmentally sustainable GW management (ESGM) needs a deep knowledge of the present and the projected status of GW (GW) quantity and quality. Translations of these data into policy relevant information are usually done through quantitative indices. Despite the availability of a dozen GW sustainability indicators, defining an integrated index based on internationally accepted scientific standards indicators is required. To fill this gap, an in-depth review on the developed indicators/index for evaluation of GW sustainable management (GWSM) from an environmental viewpoint at aquifer scales is provided in this study. Thirteen environmentally related quantitative indicators are... 

    Highly uniform molybdenum oxide loaded N-CNT as a remarkably active and selective nanocatalyst for H2S selective oxidation

    , Article Science of the Total Environment ; Volume 711 , 2020 Ghasemy, E ; Emrooz, H. B. M ; Rashidi, A ; Hamzehlouyan, T ; Sharif University of Technology
    Elsevier B.V  2020
    Selective oxidation of H2S to elemental sulfur is a low cost and highly efficient process for sulfur removal from H2S-containing hydrocarbon streams in medium scale (i.e. 0.2–10 ton sulfur/day) for environmental protection and prevention of emitting toxic gases to the atmosphere. In this research, in order to prepare a highly active and selective nanocatalyst for selective oxidation of hydrogen sulfide, for the first time, molybdenum oxides were loaded uniformly over nitrogen- doped carbon nanotubes through incipient wetness impregnation. Different metal loadings including 5, 10, and 15 wt% Mo were considered in the synthesis procedure to achieve the optimized performance and provide... 

    Multiple interactive pollutants in water quality trading

    , Article Environmental Management ; Volume 42, Issue 4 , 2008 , Pages 620-646 ; 0364152X (ISSN) Sarang, A ; Lence, B. J ; Shamsai, A ; Sharif University of Technology
    Efficient environmental management calls for the consideration of multiple pollutants, for which two main types of transferable discharge permit (TDP) program have been described: separate permits that manage each pollutant individually in separate markets, with each permit based on the quantity of the pollutant or its environmental effects, and weighted-sum permits that aggregate several pollutants as a single commodity to be traded in a single market. In this paper, we perform a mathematical analysis of TDP programs for multiple pollutants that jointly affect the environment (i.e., interactive pollutants) and demonstrate the practicality of this approach for cost-efficient maintenance of...